9.8 Bolt Torque Chart
Tightening torque and clamp force for Class 9.8 bolts from M1.6 to M16. For example, an M8 9.8 bolt needs about 29.9 N·m (22.0 ft·lb) with dry threads.
Quenched and tempered steel, defined only up to M16. Uncommon outside specific OEM applications.
- Standard
- Metric (ISO 898-1)
- Yield strength used
- 720 MPa (104 ksi)
- Tensile strength
- 900 MPa (131 ksi)
- Sizes covered
- M1.6 – M16
| Size | Threadpitch | Clamp forcepreload | Dryμ 0.15 | Oiledμ 0.11 | PTFE / moly pasteμ 0.06 |
|---|---|---|---|---|---|
| M1.6 | M1.6×0.350.35 mm | 0.64 kN144 lbf | 0.23 N·m0.17 ft·lb | 0.17 N·m0.13 ft·lb | 0.12 N·m0.09 ft·lb |
| M2 | M2×0.40.4 mm | 1.04 kN235 lbf | 0.47 N·m0.34 ft·lb | 0.35 N·m0.26 ft·lb | 0.24 N·m0.18 ft·lb |
| M2.5 | M2.5×0.450.45 mm | 1.71 kN384 lbf | 0.94 N·m0.69 ft·lb | 0.71 N·m0.52 ft·lb | 0.48 N·m0.35 ft·lb |
| M3 | M3×0.50.5 mm | 2.54 kN570 lbf | 1.61 N·m1.19 ft·lb | 1.21 N·m0.89 ft·lb | 0.81 N·m0.60 ft·lb |
| M3.5 | M3.5×0.60.6 mm | 3.41 kN768 lbf | 2.47 N·m1.82 ft·lb | 1.86 N·m1.37 ft·lb | 1.25 N·m0.93 ft·lb |
| M4 | M4×0.70.7 mm | 4.42 kN995 lbf | 3.70 N·m2.73 ft·lb | 2.79 N·m2.06 ft·lb | 1.88 N·m1.39 ft·lb |
| M5 | M5×0.80.8 mm | 7.15 kN1607 lbf | 7.19 N·m5.30 ft·lb | 5.40 N·m3.99 ft·lb | 3.62 N·m2.67 ft·lb |
| M6 | M6×11 mm | 10.1 kN2280 lbf | 12.4 N·m9.16 ft·lb | 9.36 N·m6.90 ft·lb | 6.29 N·m4.64 ft·lb |
| M7 | M7×11 mm | 14.5 kN3270 lbf | 20.1 N·m14.8 ft·lb | 15.1 N·m11.1 ft·lb | 10.0 N·m7.39 ft·lb |
| M8 | M8×1.251.25 mm | 18.5 kN4148 lbf | 29.9 N·m22.0 ft·lb | 22.4 N·m16.6 ft·lb | 15.0 N·m11.1 ft·lb |
| M10 | M10×1.51.5 mm | 29.2 kN6570 lbf | 58.5 N·m43.1 ft·lb | 43.8 N·m32.3 ft·lb | 29.2 N·m21.6 ft·lb |
| M12 | M12×1.751.75 mm | 42.5 kN9548 lbf | 100.3 N·m74.0 ft·lb | 75.2 N·m55.5 ft·lb | 50.1 N·m36.9 ft·lb |
| M14 | M14×22 mm | 58.2 kN13080 lbf | 159.5 N·m117.7 ft·lb | 119.5 N·m88.1 ft·lb | 79.5 N·m58.6 ft·lb |
| M16 | M16×22 mm | 79.0 kN17751 lbf | 244.4 N·m180.3 ft·lb | 182.2 N·m134.4 ft·lb | 119.9 N·m88.4 ft·lb |
| Size | Threadpitch | Clamp forcepreload | Dryμ 0.15 | Oiledμ 0.11 | PTFE / moly pasteμ 0.06 |
|---|---|---|---|---|---|
| M1.6 | M1.6×0.20.2 mm | 0.79 kN178 lbf | 0.27 N·m0.20 ft·lb | 0.20 N·m0.15 ft·lb | 0.13 N·m0.10 ft·lb |
| M2 | M2×0.250.25 mm | 1.23 kN277 lbf | 0.53 N·m0.39 ft·lb | 0.40 N·m0.29 ft·lb | 0.26 N·m0.19 ft·lb |
| M2.5 | M2.5×0.350.35 mm | 1.87 kN420 lbf | 1.01 N·m0.74 ft·lb | 0.75 N·m0.55 ft·lb | 0.49 N·m0.36 ft·lb |
| M3 | M3×0.350.35 mm | 2.83 kN635 lbf | 1.75 N·m1.29 ft·lb | 1.30 N·m0.96 ft·lb | 0.84 N·m0.62 ft·lb |
| M3.5 | M3.5×0.350.35 mm | 3.98 kN895 lbf | 2.78 N·m2.05 ft·lb | 2.05 N·m1.51 ft·lb | 1.33 N·m0.98 ft·lb |
| M4 | M4×0.50.5 mm | 4.94 kN1109 lbf | 4.02 N·m2.97 ft·lb | 2.99 N·m2.21 ft·lb | 1.96 N·m1.45 ft·lb |
| M5 | M5×0.50.5 mm | 8.13 kN1827 lbf | 7.91 N·m5.84 ft·lb | 5.85 N·m4.31 ft·lb | 3.79 N·m2.79 ft·lb |
| M6 | M6×0.750.75 mm | 11.1 kN2496 lbf | 13.3 N·m9.82 ft·lb | 9.91 N·m7.31 ft·lb | 6.51 N·m4.80 ft·lb |
| M7 | M7×0.750.75 mm | 15.7 kN3528 lbf | 21.3 N·m15.7 ft·lb | 15.8 N·m11.6 ft·lb | 10.3 N·m7.57 ft·lb |
| M8 | M8×11 mm | 19.7 kN4438 lbf | 31.5 N·m23.2 ft·lb | 23.4 N·m17.3 ft·lb | 15.4 N·m11.3 ft·lb |
| M10 | M10×1.251.25 mm | 30.8 kN6934 lbf | 60.9 N·m44.9 ft·lb | 45.3 N·m33.4 ft·lb | 29.8 N·m22.0 ft·lb |
| M12 | M12×1.51.5 mm | 44.4 kN9985 lbf | 103.7 N·m76.5 ft·lb | 77.3 N·m57.0 ft·lb | 50.9 N·m37.5 ft·lb |
| M14 | M14×1.51.5 mm | 62.8 kN14111 lbf | 168.8 N·m124.5 ft·lb | 125.1 N·m92.3 ft·lb | 81.5 N·m60.1 ft·lb |
| M16 | M16×1.51.5 mm | 84.3 kN18950 lbf | 256.5 N·m189.2 ft·lb | 189.4 N·m139.7 ft·lb | 122.3 N·m90.2 ft·lb |
Preload is 70% of yield. Torque per ISO 16047 / VDI 2230 for standard hex heads, with the same friction μ in the threads and under the head. Click a size for wrench size, tap drill and a worked example. Always follow the manufacturer's value where one exists.
Frequently asked questions
What is the torque for an M8 9.8 bolt?
About 29.9 N·m (22.0 ft·lb) with dry threads and 22.4 N·m (16.6 ft·lb) with oiled threads (M8×1.25, 70% of yield, clamp force 18.5 kN).
What is the torque for an M10 9.8 bolt?
About 58.5 N·m (43.1 ft·lb) with dry threads and 43.8 N·m (32.3 ft·lb) with oiled threads (M10×1.5, 70% of yield, clamp force 29.2 kN).
What is the torque for an M12 9.8 bolt?
About 100.3 N·m (74.0 ft·lb) with dry threads and 75.2 N·m (55.5 ft·lb) with oiled threads (M12×1.75, 70% of yield, clamp force 42.5 kN).